Method of making cast-metal car-wheels.



C. SHERMAN.

METHOD 0F MAKING CAST METAL CAR WHEELS. APPLICATION FILED. Nov. 22.1917.

l y 6% 3 3 m Eatented Apr. 30, 1918.

2 SHEETS-SHEET I.

C. W. SHERMAN.

METHOD OF MAKING CAST METAL CAR WHEELS. APPLICATION FILED Nov. 22, |911.

Patented Apr. 30, 1918.

2 SHEETS-SHEET 2.

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'-CLIFTUN W. SHERMAN, 0F BUFFALO, NEW YORK.

f Mn'ri'ion or MAKING caer-METAL cnn-WHEELS.

Lacasse.

Specification of Letters Patent.

Patented Apr., 30, 1913.,

Original application filed. November 3, 1914, Serial No. 870,057.Divided and this application led November To all whom t may concern:

Be it known that I, CLIFTON W. Sinn:- MAN, a citizen of the UnitedStates, residing at Buffalo, in the county of Erie 'and State of NewYork, have invented new and useful Improvements in Methods of MakingCast- Metal Car-Wheels, of which the following is a specification.; y

This invention relatesto an improvement in the method 'of making castmetal car wheels.

'Ihe invention has for its object the production of cast car wheels inwhich the formation of the different sections is suchthat the bearingsurface of the tread or rim is hard, so as to increase its wearingcapacity,

the bore of the hub is soft to permit of easilyl machining the same inorder to properly fit the axle; to distribute the metal to thesupporting plates and brackets forming the body which are of smallersectional area A than the hub and rim, so as to produce a castingwithout shrinkage strains, spongy spots or other deformationlwhich wouldimpair the strength of the casting and to eliminate formation strains.

This application is a divisionof an application filed by myself November3, 1914, Serial #870,057. i

In the accompanying drawings:

Figure'l is a vertical section of a molding flask for producing a carwheel in accordance with my invention, taken on line 1 1, Fig. `2. Fig.2 is a horizontal section taken on line 2-2, Fig. 1. p ,Fig. 3 is avertical section of a car wheel 'embodying my improvements, taken online33, Fig. 4. Fig. 4 is a bottom plan view thereof.

Similar characters of reference indicate corresponding parts throughoutthe several its lower edge with a laterally projecting annular flange 37and a body or supporting member connecting the hub and rim. The

' upper unflanged edge of the rim is arranged higher or above the upperend of the hub,

as shown in Fig. 3. Although the body or e supporting member may bevariously constructed so far as the details are concerned,

that shown in the drawings is suitable and Serial No. 203,310..

lis dished downwardly and connectedl at the outer edge of its. elevatedouter part 4 with the upper unfian-ged edge of the rim while the inneredge of the inner depressed part 5 of said plate is connected with theupper end of the hub, an annular row of outer brackets 6 connecting theunderside of the plate with the rim and terminating at their inner endsshort of the hub and an annular row of inner brackets 7 connecting theunderside of said plate with the hub and terminating at theirouter endsshort of the rim.

In addition to the innerV and outer brackets the plate is preferablyprovidedon its underside with an annular row of intermediate brackets 8which terminate at their interspaced relatively to each other andtheinner ends of the outer brackets and the outer ends of the innerbrackets overlap each other,l while the intermediate brackets overlap.the opposing ends of the inner'and outer brackets, as shown in Fig. 4.'Ihe outer brackets are preferably so constructed tliatthe sectionalarea of the same gradually increases from the outer ends toward theinner ends thereof, the inner brackets gradually increase in sectionalarea from their inner ends toward their outer ends, the intermediatebrackets gradually increase in sectional area from their outer and innerends to-ward the central parts of the same, as shown in Fig. 4, andtheplate gradually increases in sectional area `from its inner and outeredges to that part thereof intermediate of its inner and outer edges, asshown in Fig. 3. l

If desired, the plate may also be provided with an annular strengtheningbead 9 which is preferably arranged on the upper side between the huband rim and formed with the outer brackets, the inner brackets, and theintermediate brackets. Fach of the brackets is further preferablyprovided on itsopposite sides adjacent to said bead with swells or ribs,as shown at 6, 7a, 8a, for a purpose which will presently appear. Thevarious elements of the wheel just described are all formed integrally.p

VVithin the bore of the hub the same is provided with aninner chill,lining or tool piece 10 rpreferably of tubular forni and lcon,-

'ferred construction of hub lining this is structed of soft or lowcarbon steel. rlhis lining is preferably secured ,to the hub b placingthe lining within the mold in Whic the cast parts of the wheel areformed, so that a fused" joint is produced between the v hub and liningwhich knits the same together as effectively as though the same -wereconstructed in one piece of metal. To

further secure the hub and lining against longitudinal displacementrelatively to each `other the periphery of the lining is provided with aplurality of laterally projecting members 11 which are preferably in theform of annular ribs, flanges or collars and which are embedded in themetal of the hub so that the lining is securely anchored againstdisplacement. Ordinarily the pouring of mol' ten metal against or aroundcold metal, as occurs when pouring metal against the metal hub lining,would produce cracks in the casting owing to the expansion of the coldmetal which prevents proper shrinkage of the casting. rl`his difficultyis overcome in the present instance by making the hub lining collapsibleor contractible and in the preaccomplishedwby making the same of a-plurality of sectionsJ which are separated fromeach other bylongitudinal joints 10, the space or gap at each of these joints being`bridged by a longitudinal flange 11a arrim and flange are also madesolid and hardened by pouring the metal forming these parts against aheavy chill.v .The na-v ture of the metal forming the rim"section v ofthe Wheel isv such as to produce hardness or lend itself to be hardenedunder proper heat treatmentV and rapid cooling. Owing to the abovedescribed -construction-of the' wheel, the formation of the flanged rimis effected rapidly and uniformly while the pouring of the metalproceeds at a uniform rate into the mold at the hub, and during suchpouring, the formationpf the flanged rim does not begin untilpractically the en.- tire hub and the inner parts of the body are formedcomprising'the depressed inner part of the plate, the inner brackets andthe intermediatebrackets. i

A mold suitable `for producing this wheel is shown in Figs. 1 and 2 andas there shown,

`the same comprises a bottom plate 12, a-drag or nowel 13 filled withsand and resting'on the bottom plate and forming the lower section ofthe molding flask, a cope 1 4 filled with sand and forming the uppersection of the flask, an iron chill or chiller 15 arranged between thedrag and cope and forming the intermediate part of the flask, and a core16 arranged centrally in the flask. The lining 10 is placed in the moldaround the core 1G, the joints between the lining sections `at the upperand lower ends thereof being closed by the adjacent parts of the sand inthe flask and the outer longitudinal edges of these joints being closedby a wash of clay or the like.. The fluid metal is poured into thecavity formed between the several flask members through a gate or sprue17 which is formed in the central part of the cope and opens into theupper end of the hub section of the mold cavity.

The outer chill ori chiller 15 preferably forms that part of the moldwhich extends from the back or upper side of the rim` flange upwardlyacross and above the load line 18 of the wheel so that the bearingsurface of the flange and the adjacent part of the bearing surface ofthe rim which receives the wear of the load is densely formed andlhardened.

At a suitable number of places the cope of the molding flask may beprovided with risers 19 which open into the mold cavity at the lheaviestsectional area of the brackets and plate. This heavy sectional area canbe located at any suitable point between the rim and the hub, it beingthe aim to keep this area of metal molten or in a pasty con* ditionuntil the heavier rim and hub sections have congealed with theassistance of the Chillers 10 and 15 and in this way assist in relievingthe strain on the lighter plate and bracket sections.

A s the moltenl metal is poured through the sprue into the mold cavity,the same first enters the hub cavity and'begins filling the latter fromits lower end upwardly. After the lower .end of the hub has been formedthe continued rise of the metal then begins the formation of the innerbrackets and by the time the metal reaches the top ofthe hub cavity thedepressed inner part of the plate and the intermediate brackets havebeen formed. Up to this time the metal has not yet entered the rimcavity and no part of the rim or its flange and adjacent parts have beenformed. As the molten metal surrounds the cold hub lining or chill, thelatter becomes heated and tends to expand but owing to the slack jointsbetween the sec- .tions ofthe lining, the latter is contracted aan,

elevated ends bf the outer bracket cavities, the continued inflow ofmetal through the sprue. causes the metal thenceforth to flow rapidlydownwardly and outwardly through theouter bracket cavities and lill therim cavity so that the. rim quickly forms with the outer brackets andwhen the metal reaches the top of the rim the outer elevat led part ofthe plate and the adjacent part of the intermediate brackets have alsobeen filled. ln this manner the inner part of the lwheel will be formedfirst followed by the or head of molten metal.

The above described quick and uniform formation of the flanged rimsection is se.- cured while themolten metal enters the mold cavity at auniform rate throughout the casting operation.

'llhe metal y lyingagainst the rim chill and hub chill shrihks,solidifies and contracts iirst i and the plates and brackets and innerside of rim Iand outer side of hub sections are properlyv fed' by thehead or surplus of reserve molten metal in the risers which flows fromthe same outwardly through the outer brackets and outer parts of theplate, bead and intermediate brackets to the rim, and inwardly throughthe inner brackets and inner 4parts of the plate to the hub, therebycompensating or allowing for any shrinkage and contraction in the metalforming the plate, rim and hub and preventing the formation of anydefects which would weaken or aHect the strength of the wheel, such asshrinkage holes7 spongy spots or piping. rllhe pressure of molten metaltends to strain the congealedy circular rim section. This combined withthe resistance of the congealed plate section during the coolingperiodftends to form vertical cracks on the bearing surface of the rimor tread commonly known as chill cracks. The cavity in the mold formingthe bead serves as agate for obtaining ...a proper distribution of themetal from the heads to all the bracket-s and all parts of the platesection and the inner part of the rim and the outer part of the hb, andin the finished wheel the bead formed in the bead cavitymateriallystrengthens the wheel. The movement of the vmetal from the risers to therim and hub in the manner described is facilitated by the gradualenlargement of the sectional area of the mold cavity from the rim'cavity inwardly toward the risers and from the hub cavity outwardlytoward the risers, this being secured by enlarging` the plate from thehub and rim toward the risers, as shown in Figs. i and 3, enlarging ithe outer brackets inwardly, enlarging the inner brackets outwardly,enlarging the in? Figs 2 and l, and by the cavities forming the swells6a, 7*l and 8a on the brackets, thereby allowing proper contraction ofthe rim section in its congealed state and avoiding the defectivedeformation of vertical chill cracks in the face of the tread.- .Thisenlargement of the plate brackets also tends to slow up the setting ofthe metal contained therein which allows the circumferential and radialshrinkage and contraction of the previously congealed tread section totake place without producing defects known as chill cracks.l

The objects of this increased sectional area ofthe plate and bracket arethus attained, one to properly assist in feeding the molten metal to theplate and bracketv sections adjacent to the rim, and the other to keepthis sectional area-molten so that the rim section can properlycontract.

The chilling of the tread increases the density .of the metal therein aswell as the hardness thereof. rl`he chilling of the hub with` lighterchiller only increases the density of the metal in the same because inthe proper formation the hub should be soft and strong. ln themanufacture of a wheel ofl this kind,

a h igh carbon metal is preferably employed which will produce steel toohard for easy l machining. The use of an innerfhub lining o r'chlllmadeof soft steel is therefore desirable 1n order tofacilitate the boring ormachining of the hub so that the wheel may be Iproperly fitted on itsaxle. A secondary object of the chill lining in the hub is to increasethe density of metal in the hub, not its hardness, thereby avoidingtheuse of heavy gates'or risers, because it will tend to cool th1s heavysection of metal quickly and thereby make a uniform and dense casting ofthe hub. l

lt will be apparent from the foregoing that a car wheel made inaccordance with .my invention will be practically free from any defectsdue to shrinkage strains or other improper formation or conditions whichare present in wheels made in accordance with the method heretoforecommonly practised. My improved. wheel is therefore much stronger-andsafer and these advantages are' secured in addition .to a materialdecrease in cost of the same.

I claim as my invention:

1. The hereindescribed method of making car wheels consisting iinpouring the bearing face of the rim against a chill of metal and pouringthe hub against a lining of relatively soft metal.

2. 'lhe hereindescribed method of making the weight of the wheel andtherefore in the car wheels consisting in pouring the bearing Y face ofthe .rim against a chill of metal and pouring the hub against a liningof relatively the rim and hub are cast and so constructing themold thatits sectional area gradually increases from said rim and hub portions ofthev cavity toward said risers.

4. The hereindescribed method of making integral cast metal car wheelshaving a hub, a rim, a plate connecting the hub and rim and having adepressed inner part and an elevated outer part, inner bracketsconnectin the depressed part of the plate andthe hui,` and outerbrackets connecting the ele- Vated part of the plate and the rim,consisting in first casting the hub, inner brackets and depressed partof the plate and`y then casting the outer elevated part of the plate,the outer brackets and the rim during a uni-v form curing of the moltenmetal.

5. he hereindescribed method of making an integral cast metal car wheelwhich consists in first casting the `entire hub and inner part of thesupporting body and immediately masas thereafter casting the outer partof the sup porting body and the rim of the wheel.

6. The hereindescribed method of making integral cast metal car wheelshaving a hub, a rim, a plate connecting the hub and rim, inner bracketsconnecting the inner part of the plate and hub and outer bracketsconnecting the outer part of the plate and the rim, consisting in firstcasting the hub7 inner brackets and inner part of the plate followedimmediately thereafter by the casting of the outer brackets, outer partof the plate and the rim.

7. rIhe hereindescribed method of making cast metal car wheels having ahub, a rim, a plate connecting the hub and rim, inner bracketsconnecting the inner part of the plate and hub and outer bracketsconnecting the outer part of the plate and the rim, consisting in firstcasting the hub, inner brackets and inner part of the plate followedimmediately thereafter by the casting of the outer brackets, outer partof the plate and the rim during an uninterrupted and uniform pouring ofthe metal into the mold.

8. rlhe hereindescribed method of making integral cast metal car wheelshaving a hub, a rim, anda supporting body connecting the hub and rim,consisting in first casting the entire hub and inner -part o'f thesupportingA body and then casting the outer part of the supporting bodyand the rim.

CLIFTON W. SHERMAN.

